Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 104
Filtrar
2.
Vaccines (Basel) ; 12(8)2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-39204044

RESUMO

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), emerged as a global outbreak in 2019, profoundly affecting both human health and the global economy. Various vaccine modalities were developed and commercialized to overcome this challenge, including inactivated vaccines, mRNA vaccines, adenovirus vector-based vaccines, and subunit vaccines. While intramuscular vaccines induce high IgG levels, they often fail to stimulate significant mucosal immunity in the respiratory system. We employed the Newcastle disease virus (NDV) vector expressing the spike protein of the SARS-CoV-2 Beta variant (rK148/beta-S), and evaluated the efficacy of intranasal vaccination with rK148/beta-S in K18-hACE2 transgenic mice. Intranasal vaccination with a low dose (106.0 EID50) resulted in an 86% survival rate after challenge with the SARS-CoV-2 Beta variant. Administration at a high dose (107.0 EID50) led to a reduction in lung viral load and 100% survival against the SARS-CoV-2 Beta and Delta variants. A high level of the SARS-CoV-2 spike-specific IgA was also induced in vaccinated mice lungs following the SARS-CoV-2 challenge. Our findings suggest that rK148/beta-S holds promise as an intranasal vaccine candidate that effectively induces mucosal immunity against SARS-CoV-2.

3.
Int J Mol Sci ; 25(12)2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38928513

RESUMO

Arterial macrophage cholesterol accumulation and impaired cholesterol efflux lead to foam cell formation and the development of atherosclerosis. Modified lipoproteins interact with toll-like receptors (TLR), causing an increased inflammatory response and altered cholesterol homeostasis. We aimed to determine the effects of TLR antagonists on cholesterol efflux and foam cell formation in human macrophages. Stimulated monocytes were treated with TLR antagonists (MIP2), and the cholesterol efflux transporter expression and foam cell formation were analyzed. The administration of MIP2 attenuated the foam cell formation induced by lipopolysaccharides (LPS) and oxidized low-density lipoproteins (ox-LDL) in stimulated THP-1 cells (p < 0.001). The expression of ATP-binding cassette transporters A (ABCA)-1, ABCG-1, scavenger receptor (SR)-B1, liver X receptor (LXR)-α, and peroxisome proliferator-activated receptor (PPAR)-γ mRNA and proteins were increased (p < 0.001) following MIP2 administration. A concentration-dependent decrease in the phosphorylation of p65, p38, and JNK was also observed following MIP2 administration. Moreover, an inhibition of p65 phosphorylation enhanced the expression of ABCA1, ABCG1, SR-B1, and LXR-α. TLR inhibition promoted the cholesterol efflux pathway by increasing the expression of ABCA-1, ABCG-1, and SR-B1, thereby reducing foam cell formation. Our results suggest a potential role of the p65/NF-kB/LXR-α/ABCA1 axis in TLR-mediated cholesterol homeostasis.


Assuntos
Transportador 1 de Cassete de Ligação de ATP , Colesterol , Células Espumosas , Lipoproteínas LDL , Receptores X do Fígado , Receptores Toll-Like , Humanos , Células Espumosas/metabolismo , Células Espumosas/efeitos dos fármacos , Colesterol/metabolismo , Receptores X do Fígado/metabolismo , Receptores Toll-Like/metabolismo , Transportador 1 de Cassete de Ligação de ATP/metabolismo , Transportador 1 de Cassete de Ligação de ATP/genética , Lipoproteínas LDL/metabolismo , Lipoproteínas LDL/farmacologia , PPAR gama/metabolismo , Células THP-1 , Macrófagos/metabolismo , Macrófagos/efeitos dos fármacos , Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Membro 1 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/genética , Lipopolissacarídeos/farmacologia , Receptores Depuradores Classe B/metabolismo , Receptores Depuradores Classe B/genética
4.
Vaccine ; 42(18): 3756-3767, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38724417

RESUMO

A Newcastle disease virus (NDV)-vectored vaccine expressing clade 2.3.4.4b H5 Hemagglutinin was developed and assessed for efficacy against H5N1 highly pathogenic avian influenza (HPAI) in specific pathogen-free (SPF) chickens, broilers, and domestic ducks. In SPF chickens, the live recombinant NDV-vectored vaccine, rK148/22-H5, achieved complete survival against HPAI and NDV challenges and significantly reduced viral shedding. Notably, the live rK148/22-H5 vaccine conferred good clinical protection in broilers despite the presence of maternally derived antibodies. Good clinical protection was observed in domestic ducks, with decreased viral shedding. It demonstrated complete survival and reduced cloacal viral shedding when used as an inactivated vaccine from SPF chickens. The rK148/22-H5 vaccine is potentially a viable and supportive option for biosecurity measure, effectively protecting in chickens against the deadly clade 2.3.4.4b H5 HPAI and NDV infections. Furthermore, it aligns with the strategy of Differentiating Infected from Vaccinated Animals (DIVA).


Assuntos
Anticorpos Antivirais , Galinhas , Patos , Glicoproteínas de Hemaglutininação de Vírus da Influenza , Virus da Influenza A Subtipo H5N1 , Influenza Aviária , Vírus da Doença de Newcastle , Vacinas de Produtos Inativados , Vacinas Sintéticas , Eliminação de Partículas Virais , Animais , Galinhas/imunologia , Influenza Aviária/prevenção & controle , Influenza Aviária/imunologia , Vírus da Doença de Newcastle/imunologia , Vírus da Doença de Newcastle/genética , Virus da Influenza A Subtipo H5N1/imunologia , Virus da Influenza A Subtipo H5N1/genética , Virus da Influenza A Subtipo H5N1/patogenicidade , Patos/virologia , Patos/imunologia , Vacinas de Produtos Inativados/imunologia , Vacinas de Produtos Inativados/administração & dosagem , Vacinas Sintéticas/imunologia , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/genética , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/sangue , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Vacinas contra Influenza/imunologia , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/genética , Organismos Livres de Patógenos Específicos , Vacinas Atenuadas/imunologia , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/genética , Doenças das Aves Domésticas/prevenção & controle , Doenças das Aves Domésticas/virologia , Doenças das Aves Domésticas/imunologia , Doença de Newcastle/prevenção & controle , Doença de Newcastle/imunologia , Vacinas Virais/imunologia , Vacinas Virais/administração & dosagem , Vacinas Virais/genética
5.
J Dent ; 148: 105054, 2024 09.
Artigo em Inglês | MEDLINE | ID: mdl-38796091

RESUMO

OBJECTIVES: To create bacteria-resistant dental CAD-CAM blocks with a biofilm-resistant effect by incorporating Nano-crystalline ceramic and polymer (NCP) with 2-methacryloyloxyethyl phosphorylcholine (MPC) and sulfobetaine methacrylate (SBMA) and at an equimolar ratio, referred to as MS. METHODS: Experimental groups comprised NCP blocks containing zwitterions at 0.15wt% (MS015) and 0.45wt% (MS045). NCP blocks without MS served as control (CTRL). Flexural strength, surface hardness, water sorption and solubility, photometric properties, and cytotoxicity were assessed for all samples. Additionally, the resistance to single and multi-species bacterial adhesion was investigated. RESULTS: MS045 showed significant reduction in flexural strength (P < 0.01) compared to both CTRL and MS015. Both MS015 and MS045 showed significantly increased water sorption and significant reduction in water solubility compared to CTRL. Light transmission remained consistent across all MS content levels, but the irradiance value decreased by 12 % in the MS045 group compared to the MS015 group. Notably, compared to the CTRL group, the MS015 group exhibited enhanced resistance to adhesion by Porphyromonas gingivalis and a multi-species salivary biofilm, with biofilm thickness and biomass reduced by 45 % and 56 %, respectively. CONCLUSIONS: NCP containing 0.15 % MS can effectively reduce adhesion of multiple species of bacteria while maintaining physical and mechanical properties. CLINICAL SIGNIFICANCE: NCP integrating zwitterions is clinically advantageous in resisting bacterial adhesion at internal and external margins of milled indirect restoration.


Assuntos
Aderência Bacteriana , Biofilmes , Cerâmica , Desenho Assistido por Computador , Resistência à Flexão , Teste de Materiais , Metacrilatos , Fosforilcolina , Propriedades de Superfície , Cerâmica/química , Metacrilatos/química , Aderência Bacteriana/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Fosforilcolina/análogos & derivados , Fosforilcolina/química , Fosforilcolina/farmacologia , Materiais Dentários/química , Polímeros/química , Humanos , Dureza , Solubilidade , Porphyromonas gingivalis/efeitos dos fármacos
6.
Am J Pathol ; 194(7): 1306-1316, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38588851

RESUMO

The role of the phosphatidylinositol 3-kinase (PI3K)/Akt pathway in renal cell carcinoma (RCC) progression, metastasis, and resistance to therapies has not been investigated thoroughly. Transcription factor E3 (TFE3) expression is related to a poorer prognosis and tumor microenvironment in patients with RCC. This study aimed to determine the relationship between TFE3 and the PI3K/Akt pathway. TFE3 down-regulation was achieved by transient transfection of siRNA and shRNA in UOK146 cells. TFE3 overexpression was induced by transient transfection with pcDNA3.1 encoding the constitutively active form of TFE3. The cells were treated with mammalian target of rapamycin (mTOR) and PI3K inhibitors. Western blot was performed to detect TFE3, programmed death-ligand 1, phospho-Akt, and Akt. Phospho-Akt expression increased significantly upon TFE3 down-regulation, and decreased significantly upon up-regulation. When RCC cells were treated with a PI3K inhibitor (LY294002), TFE3 expression increased and phospho-Akt expression decreased. Data from this study indicate that TFE3 plays a role in the PI3K/Akt pathway in RCC. The results of this study suggest that PI3K/Akt inhibitors may aid in the treatment of patients with RCC by affecting the tumor microenvironment.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos , Carcinoma de Células Renais , Neoplasias Renais , Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Serina-Treonina Quinases TOR , Microambiente Tumoral , Humanos , Carcinoma de Células Renais/patologia , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/genética , Serina-Treonina Quinases TOR/metabolismo , Microambiente Tumoral/fisiologia , Neoplasias Renais/patologia , Neoplasias Renais/metabolismo , Neoplasias Renais/genética , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/fisiologia , Linhagem Celular Tumoral , Fosfatidilinositol 3-Quinases/metabolismo , Regulação Neoplásica da Expressão Gênica
7.
Virus Evol ; 10(1): veae014, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38455682

RESUMO

Clade 2.3.4.4b highly pathogenic avian influenza A (HPAI) viruses have been detected in wild birds worldwide, causing recurrent outbreaks since 2016. During the winter of 2021-2022, we detected one H5N8 and forty-three H5N1 clade 2.3.4.4b HPAI viruses from wild birds in South Korea. Phylogenetic analysis revealed that HA gene of H5N1 viruses was divided into two genetically distinct groups (N1.G1 and N1.G2). Bayesian phylodynamic analysis demonstrated that wild birds play a vital role in viral transmission and long-term maintenance. We identified five genotypes (N1.G1.1, N1.G2, N1.G2.1, N1.G2.2, and N1.G2.2.1) having distinct gene segment constellations most probably produced by reassortments with low-pathogenic avian influenza viruses. Our results suggest that clade 2.3.4.4b persists in wild birds for a long time, causing continuous outbreaks, compared with previous clades of H5 HPAI viruses. Our study emphasizes the need for enhancing control measures in response to the changing viral epidemiology.

9.
Infect Genet Evol ; 118: 105565, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38309607

RESUMO

Infectious bronchitis virus (IBV), an avian coronavirus, has caused considerable damage to the poultry industry. In Korea, indigenous KM91-like and newly introduced QX-like lineages belonging to the GI-19 lineage have been prevalent despite constant vaccination. In this study, complete genome sequences of 23 IBV isolates in Korea from 2010 to 2020 were obtained using next-generation sequencing, and their phylogenetic relationship and recombination events were analyzed. Phylogenetic analysis based on the S1 gene showed that all isolates belonged to the GI-19 lineage and were divided into five subgroups (KM91-like, K40/09-like, and QX-like II to IV). Among the 23 isolates, 14 recombinants were found, including frequent recombination between KM91-like and QX-like strains. In addition, it was observed that other lineages, such as GI-1, GI-13, and GI-16, were involved in recombination. Most recombination breakpoints were detected in the ORF1ab gene, particularly nsp3. However, when considering the size of each genome, recombination occurred more frequently in the 3a, E and 5a genes. Taken together, genetic recombination frequently occurred throughout the entire genome between various IBV strains in Korea, including live attenuated vaccine strain. Our study suggests the necessity of further research on the contribution of recombination of genomes outside the spike region to the biological characteristics of IBV.


Assuntos
Gammacoronavirus , Vírus da Bronquite Infecciosa , Filogenia , República da Coreia/epidemiologia , Vírus da Bronquite Infecciosa/genética , Vacinas Atenuadas , Recombinação Genética
10.
Virology ; 590: 109945, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38064871

RESUMO

The ongoing COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has led to the emergency of various lineages through mutations and recombination. In the Delta lineage, we identified recombination events in the ORF1a gene, which divided the Delta sublineages into three different genotypes (Delta R1-R3). The regional distributions of Delta R1 and Delta R2 were not correlated, indicating that recombination occurred early in the Delta outbreak. The impact of the ORF1a gene on SARS-CoV-2 transmission remains unclear; however, our findings suggest that recombination may have contributed to the evolution and global spread of the Delta lineage.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/epidemiologia , Pandemias , Surtos de Doenças
11.
Front Vet Sci ; 10: 1157984, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37377949

RESUMO

Avian influenza viruses (AIVs) in wild birds are phylogenetically separated in Eurasian and North American lineages due to the separated distribution and migration of wild birds. However, AIVs are occasionally dispersed between two continents by migratory wild birds flying across the Bering Strait. In this study, we isolated three AIVs from wild bird feces collected in South Korea that contain gene segments derived from American lineage AIVs, including an H6N2 isolated in 2015 and two H6N1 in 2017. Phylogenetic analysis suggests that the H6N2 virus had American lineage matrix gene and the H6N1 viruses had American lineage nucleoprotein and non-structural genes. These results highlight that novel AIVs have continuously emerged by reassortment between viruses from the two continents. Therefore, continuous monitoring for the emergence and intercontinental spread of novel reassortant AIV is required to prepare for a possible future outbreak.

12.
Emerg Microbes Infect ; 12(2): 2228934, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37345516

RESUMO

Following the global emergence of the SARS-CoV-2 Alpha variant of concern (VOC) in 2020, the Delta variant triggered another wave in 2021. The AY.69 lineage, a Delta VOC, was particularly prevalent in Republic of Korea (South Korea) from May 2021 to January 2022, despite the synchronized implementation of vaccination programmes and non-pharmaceutical interventions (NPIs) such as social distancing. In this study, we used phylogeographic analysis combined with a generalized linear model (GLM) to examine the impact of human movement and vaccination on viral transmission. Our findings indicated that transmission primarily originated in South Korea's metropolitan areas, and a positive correlation was observed between total human mobility (tracked by GPS on mobile phones and estimated through credit card consumption) and viral spread. The phylodynamic analysis further revealed that non-vaccinated individuals were the primary transmitters of the virus during the study period, even though vaccination programmes had commenced three months prior to the AY.69 outbreak. Our study emphasizes the need to focus on controlling SARS-CoV-2 transmission in metropolitan regions and among unvaccinated populations. Furthermore, the positive correlation between mobility data and viral dissemination could contribute to the development of more accurate predictive models for local spread of pandemics.


Assuntos
COVID-19 , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , SARS-CoV-2/genética , República da Coreia/epidemiologia , Vacinação
13.
Vaccine ; 41(33): 4787-4797, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37355454

RESUMO

Coronavirus disease 2019 (Covid-19) caused by the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) became a pandemic, causing significant burden on public health worldwide. Although the timely development and production of mRNA and adenoviral vector vaccines against SARS-CoV-2 have been successful, issues still exist in vaccine platforms for wide use and production. With the potential for proliferative capability and heat stability, the Newcastle disease virus (NDV)-vectored vaccine is a highly economical and conceivable candidate for treating emerging diseases. In this study, a recombinant NDV-vectored vaccine expressing the spike (S) protein of SARS-CoV-2, rK148/beta-S, was developed and evaluated for its efficacy against SARS-CoV-2 in K18-hACE-2 transgenic mice. Intramuscular vaccination with low dose (106.0 EID50) conferred a survival rate of 76 % after lethal challenge of a SARS-CoV-2 beta (B.1.351) variant. When administered with a high dose (107.0 EID50), vaccinated mice exhibited 100 % survival rate and reduced lung viral load against both beta and delta variants (B.1.617.2). Together with the protective immunity, rK148/beta-S is an accessible and cost-effective SARS-CoV-2 vaccine.


Assuntos
COVID-19 , Vacinas Virais , Camundongos , Animais , Humanos , COVID-19/prevenção & controle , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/genética , Vacinas contra COVID-19 , Vírus da Doença de Newcastle/genética , Camundongos Transgênicos , Vacinas Virais/genética , Anticorpos Antivirais , Anticorpos Neutralizantes
14.
Omega (Westport) ; : 302228231177847, 2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37220767

RESUMO

Posttraumatic growth (PTG) is a positive psychological change experienced after trauma and it has gained global recognition in recent years. The present study aimed to validate a South Korean version of the Posttraumatic Growth Inventory-Expanded (K-PTGI-X) for use with trauma-exposed and bereaved samples. A national sample comprising South Korean adults was used for the analysis. As a result, the 4-factor bi-factor model was best supported in both the trauma and bereaved groups in terms of personal strength, new possibilities, spiritual-existential change, and being able to relate to others. Additionally, the K-PTGI-X showed satisfying reliability, concurrent validity, and discriminant validity. Lastly, regarding the group differences, women showed higher rates of PTG than men and the bereaved group exhibited higher spiritual and existential growth in the PTG than the trauma group. Given these results, implications for adaptation in various fields when assessing and encouraging PTG in practical settings are discussed.

15.
Sensors (Basel) ; 23(3)2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36772389

RESUMO

In this study, the Convolution Neural Network (CNN) algorithm is applied for non-destructive evaluation of aluminum panels. A method of classifying the locations of defects is proposed by exciting an aluminum panel to generate ultrasonic Lamb waves, measuring data with a sensor array, and then deep learning the characteristics of 2D imaged, reflected waves from defects. For the purpose of a better performance, the optimal excitation location and sensor locations are investigated. To ensure the robustness of the training model and extract the feature effectively, experimental data are collected by slightly changing the excitation frequency and shifting the location of the defect. The high classification accuracy for each defect location can be achieved. It is found that the proposed algorithm is also successfully applied even when a bar is attached to the panel.

16.
Biomol Ther (Seoul) ; 31(3): 319-329, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36382510

RESUMO

Resistance to hypomethylating agents (HMAs) in myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML) is a concerning problem. Polo-like kinase 1 (PLK1) is a key cell cycle modulator and is known to be associated with an activation of the PI3K pathway, which is related to the stabilization of DNA methyltransferase 1 (DNMT1), a target of HMAs. We investigated the effects of volasertib on HMA-resistant cell lines (MOLM/AZA-1 and MOLM/DEC-5) derived from MOLM-13, and bone marrow (BM) samples obtained from patients with MDS (BM blasts >5%) or AML evolved from MDS (MDS/AML). Volasertib effectively inhibited the proliferation of HMA-resistant cells with suppression of DNMTs and PI3K/AKT/mTOR and ERK pathways. Volasertib also showed significant inhibitory effects against primary BM cells from patients with MDS or MDS/AML, and the effects of volasertib inversely correlated with DNMT3B expression. The DNMT3B-overexpressed AML cells showed primary resistance to volasertib treatment. Our data suggest that volasertib has a potential role in overcoming HMA resistance in patients with MDS and MDS/AML by suppressing the expression of DNMT3 enzymes and PI3K/AKT/mTOR and ERK pathways. We also found that DNMT3B overexpression might be associated with resistance to volasertib.

17.
Sci Rep ; 12(1): 22414, 2022 12 27.
Artigo em Inglês | MEDLINE | ID: mdl-36575217

RESUMO

The outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global pandemic since 2019. Variants of concern (VOCs) declared by the World Health Organization require continuous monitoring because of their possible changes in transmissibility, virulence, and antigenicity. The Omicron variant, a VOC, has become the dominant variant worldwide since November 2021. In the Republic of Korea (South Korea), the number of confirmed cases increased rapidly after the detection of Omicron VOC on November 24, 2021. In this study, we estimated the underlying epidemiological processes of Omicron VOC in South Korea using time-scaled phylodynamic analysis. Three distinct phylogenetic subgroups (Kor-O1, Kor-O2, and Kor-O3) were detected in South Korea. The Kor-O1 subgroup circulated in the Daegu region, whereas Kor-O2 and Kor-O3 circulated in Incheon and Jeollanam-do, respectively. The viral population size and case number of the Kor-O1 subgroup increased more rapidly than those of the other subgroups, indicating the rapid spread of the virus. The results indicated the multiple introductions of Omicron sub-lineages into South Korea and their subsequent co-circulation. The evolution and transmission of SARS-CoV-2 should be continuously monitored, and control strategies need to be improved to control the multiple variants.


Assuntos
COVID-19 , Humanos , Filogenia , COVID-19/epidemiologia , SARS-CoV-2/genética , Genômica , República da Coreia/epidemiologia
18.
Heliyon ; 8(10): e11004, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36276757

RESUMO

Acute myeloid leukemia (AML) is an aggressive blood cancer with a high rate of relapse associated with adverse survival outcomes, especially in elderly patients. An aberrant expression of cyclin dependent kinase 7 (CDK7) is associated with poor outcomes and CDK7 inhibition has showed antitumor activities in various cancers. We investigated the efficacy of YPN-005, a CDK7 inhibitor in AML cell lines, xenograft mouse model, and primary AML cells. YPN-005 effectively inhibited the proliferation of AML cells by inducing apoptosis and reducing phosphorylation of RNA polymerase II. The c-MYC expression decreased with treatment of YPN-005, and the effect of YPN-005 was negatively correlated with c-MYC expression. YPN-005 also showed antileukemic activities in primary AML cells, especially those harboring FMS-like tyrosine kinase 3-internal tandem duplication (FLT3-ITD) mutation and in in vivo mouse model. Phosphorylated FLT3/Signal transducer and activator of transcription 5 (STAT5) was decreased and FLT3/STAT5 was downregulated with YPN-005 treatment. Our data suggest that YPN-005 has a role in treating AML by suppressing c-MYC and FLT3.

19.
J Plant Physiol ; 270: 153633, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35151953

RESUMO

During multicellularization, plants evolved unique cell-cell connections, the plasmodesmata (PD). PD of angiosperms are complex cellular domains, embedded in the cell wall and consisting of multiple membranes and a large number of proteins. From the beginning, it had been assumed that PD provide passage for a wide range of molecules, from ions to metabolites and hormones, to RNAs and even proteins. In the context of assimilate allocation, it has been hypothesized that sucrose produced in mesophyll cells is transported via PD from cell to cell down a concentration gradient towards the phloem. Entry into the sieve element companion cell complex (SECCC) is then mediated on three potential routes, depending on the species and conditions, - either via diffusion across PD, after conversion to raffinose via PD using a polymer trap mechanism, or via a set of transporters which secrete sucrose from one cell and secondary active uptake into the SECCC. Multiple loading mechanisms can likely coexist. We here review the current knowledge regarding photoassimilate transport across PD between cells as a prerequisite for translocation from leaves to recipient organs, in particular roots and developing seeds. We summarize the state-of-the-art in protein composition, structure, transport mechanism and regulation of PD to apprehend their functions in carbohydrate allocation. Since many aspects of PD biology remain elusive, we highlight areas that require new approaches and technologies to advance our understanding of these enigmatic and important cell-cell connections.

20.
Virus Evol ; 7(2): veab077, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34760282

RESUMO

Genomic epidemiology is a core component in investigating the spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this study, the efficacy of control strategies in South Korea was evaluated using genomic epidemiology based on viral genome sequences of 2,065 SARS-CoV-2 cases identified in South Korea from January 2020 to December 2020. Phylogenetic analysis revealed that the majority of viruses introduced from inbound travelers did not further spread throughout South Korea; however, four distinct subgroups (KR.1-4, belonging to B.1.497, B.1, K.1 and B.41) of viruses caused local epidemics. After the introduction of enhanced social distancing, the viral population size and daily case numbers decreased, and KR.2-4 subgroups were extinguished from South Korea. Nevertheless, there was a subsequent increase in KR.1 subgroups after the downgrading of social distancing level. These results indicate that the international traveler quarantine system implemented in South Korea along with social distancing measures efficiently reduced the introduction and spread of SARS-CoV-2, but it was not completely controlled. An improvement of control strategies will be required to better control SARS-CoV-2, its variants, and future pandemic viruses.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA